| Cystic lung disease | Distinctive clinical features | Typical CT features* | Confirmation of diagnosis (in association with compatible chest CT) |
| LAM | - Occurs almost exclusively in females (occasionally in males with TSC)
- Renal angiomyolipomas in up to 50% of cases
- Retroperitoneal or pelvic lymphangioleiomyomas
- Chylous effusion, chylous ascites
- May be accompanied by clinical features of TSC
| - Small, thin-walled, round cysts varying little in size or shape, uniformly distributed throughout the lungs
| One of the following: - Noncontrast abdomen/pelvis CT or MRI demonstrating renal angiomyolipoma or cystic lymphangioleiomyoma
- Presence of chylous pleural effusion or ascites¶
- Serum VEGF-D >800 pg/mL
- Presence of TSC
- Transbronchial or surgical lung biopsy demonstrating diagnostic histological featuresΔ (if all of the above are absent)
|
| PLCH | - Nearly all affected individuals are current or former cigarette smokers◊
- Diabetes insipidus
- Bone lesions
| - Mix of nodules and thick-walled cysts (early stages) or bizarrely shaped cysts varying in size and shape (advanced stages)
- Upper and mid-lung zone distribution with sparing of costophrenic angles
| One of the following: - BAL with ≥5% CD1a-positive cells
- Transbronchial or surgical lung biopsy demonstrating diagnostic histological features
|
| BHD | - Fibrofolliculomas
- Renal neoplasms, typically multifocal hybrid oncocytic tumors or chromophobe renal cell carcinomas
- Family history of pneumothorax or renal neoplasms
| - Bilateral thin-walled round or lentiform cysts of variable sizes, often subpleural and/or abutting the mediastinum, with a lower lung zone predominance
| One of the following: - Biopsy-proven skin fibrofolliculoma
- Bilateral, multifocal hybrid oncocytic renal tumors or chromophobe renal cell carcinomas
- Genetic testing positive for FLCN mutation
NOTE: Lung biopsy NOT helpful |
| LIP | - Underlying autoimmune or immunodeficiency state in 80% of cases
- Sjögren syndrome is most common underlying disorder
| - Thin-walled cysts, typically few in number, associated with ground glass opacities and centrilobular nodules
| - Serologic testing for HIV and systemic rheumatic disease (eg, antinuclear antibody, anti-Ro/SSA, anti-La/SSB, rheumatoid factor) adds support to clinical diagnosis
- Lacrimal gland or lip biopsy
- Surgical lung biopsy, when a definitive diagnosis is needed to guide therapy
NOTE: Transbronchial biopsy size too small to be definitive for LIP, so TBLB only helpful if an alternate diagnosis suspected (eg, LAM) |
